This invention relates to an illumination case used for decoration or advertisement. This invention is an improvement of China Patent ZL00227988. 6, xe2x80x9cNovel Lamp Casexe2x80x9d.
The illumination case design of the xe2x80x9cNovel Lamp Casexe2x80x9d is based on the method that uses the relative movement of a grating plate to an illumination filmstrip to cause the appearance that pictures on the illumination case are changing or moving. The included grating plate is pressed close to the illumination filmstrip. It is fitted with a set of stretch springs at both the upper side and bottom side, which link to the inner frame to make it spread. Step motors drive the grating plate to move up and down with the transmission located at its upper or lower side, one for the left side, and another for the right side.
The above-mentioned xe2x80x9cNovel Lamp Casexe2x80x9d has a novel and simple structure with a reduced cost. However, it also has some shortcomings. The upper side and bottom side are tensioned and are spread directly by the stretch springs. Due to the single direction of spring tension, it is difficult for the grating plate to press close to the illumination filmstrip. As a result, the gap formed between the grating plate and the illumination filmstrip is locally too big, which generates false images causing imperfect picture effects from the illumination case. The step motors and the stretch springs are placed at the top and bottom side of the grating plate, which creates a larger length in the vertical direction.
Therefore, there is a need to improve upon the prior invention and create better picture effects while also shortening the size of the illumination case.
The present invention satisfies these needs. The object of this invention is to overcome the above-mentioned shortcomings of the lamp case and provide an improved illumination case that can effectively eliminate false images of the illumination case""s picture and reduce the size of the illumination case.
The object of this invention is realized through the measures described below. The improved illumination case includes a case-body, a front cover, an inner frame, a light source, a transparent back plate, an illumination filmstrip, a grating plate, and two step motors with a transmission that drives the grating plate to move up and down.
The transparent back plate is fixed onto the inner frame. The illumination filmstrip overlays the transparent back plate and is fixed against it. Two step motors, as mentioned above, are installed on the inner frame behind the upper part or lower part of the transparent back plate, one on the left side, and the other on the right side. The above-mentioned grating plate is fitted with a hanging bar on both the upper side and bottom side respectively, which make the grating plate spread out neatly. One hanging bar is linked with the transmissions of the two above-mentioned step motors through two corresponding levers. Through one lever, the other hanging bar connects with a set of stretch springs that is fitted onto the inner frame behind the transparent back plate. By this manner, the grating plate spreads out and presses close to the illumination filmstrip.